ENGINE DIAGNOSTIC FAQ

ENGINE DIAGNOSTIC FAQ

If you have any questions, our FAQ may help…

1. Can we know the exact mileage of an engine ?

2. What does an engine oil analysis reveal ?

3. Can we tell if an oil change was done recently ?

4. When should I do an oil analysis ?

5. What is the minimum service time for the oil to be representative of the operating condition of the engine ?

6. Can the brand of lubricant be determined ?

7. Can the standard (ACEA, API, VW, SAE, etc.) be determined on an oil ?

8. What confidence can be accorded to IESPM ?

9. What are the main reasons for which a diagnostic can be incorrect ?

10. When should I realise a sampling ?

11. Why are there no thresholds for the values in the reports ?

12. How long does it take to receive the kit ?

13. How long does it take to receive the analyses after the samples have been sent in ?

14. How can I order my oil analysis kit ?

15. Do I need to do an oil change to realise the sampling ?

16. Can we make an oil analysis on a vehicle which does not start and which did not work recently ?

 

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1. Can we know the exact mileage of an engine ?

No, like for a blood analysis, it is impossible to know the age of a patient from the results of the examination. However, we can ascertain the condition of the engine and this irrespective of its mileage.

2. What does an engine oil analysis reveal ?

Possible degradation of the lubricant caused by :

• Pollutants (especially combustion soots and unburnt fuel)
• Excessive mileage
• High-temperature operation
• Prolonged storage
• Etc.

The quality of the combustion parameters :

• Correct injection
• Dilution by fuel
• Soiling by carbon residues
• Etc.
  

Level of wear :

• Sleeve/piston
• Distribution
• Rings
• Bearings
• Turbo
• Etc.
  

Presence of external pollutants :

• Cooling liquid (sealing of cylinder head gasket, etc.)
• Condensation water
• Silica (quality of air filtering, etc.)
• Sodium (suction of spray by outboard engines, etc.)

3. Can we tell if an oil change was done recently ?

Yes. The characteristics of the oil change throughout its lifetime; it becomes charged with metallic wear particles and pollutants can appear. If no variation is observed when compared with a new oil sample, we can consider that the oil change was done recently.

4. When should I do an oil analysis ?

• Before a purchase (car, motorcycle, boat, camper van, etc.)
• Before resale (car, motorcycle, boat, camper van, etc.)
• Following the appearance of operating defects : noise, smoke, lack of power, excessive oil or fuel consumption, difficulty in starting
• At all times to follow-up or get to know the condition of your engine.

5. What is the minimum service time for the oil to be representative of the operating condition of the engine ?

During its operation, the engine frees metallic particles and contamination elements into the oil.  It is from around 3000 kilometres that we can know whether the wear and the operation of an engine are normal or not.

For other equipments such as boats, BTP (building and civil engineering works) or industrial materials, a minimum of 20 hours of service is required before taking a sample in order to get a representative analysis result.

6. Can the brand of lubricant be determined ?

Today, there is a wide variety of brands on the market and also a wide variety of formulas. However, it is not rare to encounter lubricants of different brands with the same or very similar formulas. It is therefore difficult to determine the brand of a lubricant with certainty.

However, we can :

• Indicate the type of formula (mineral, semi-synthetic, synthetic)
• Assess, according to the degree of alteration of the lubricant, the viscosity grade
• Establish a similarity by comparison between the used oil sample and a fresh oil sample

7. Can the standard (ACEA, API, VW, SAE, etc.) be determined on an oil ?

No, all the standards are obtained under clearly defined test conditions (e.g. Dynamic test, tests on engine bench, etc.) the results of which can be transposed only to new oils.

8. What confidence can be accorded to IESPM ?

IESPM was one of the first laboratories to propose this type of service to individuals and professionals. With more than 50 years of experience, it is today present in a high number of sectors of activities and its expertise is widely acknowledged. Its reports are regularly used by experts in the courts.

9. What are the main reasons for which a diagnostic can be incorrect ?

• non-representative sample
• an insufficient number of hours or mileage
• incomplete or incorrect information may lead to a poor interpretation of the analysis results
  

10. When should I realise a sampling ?

Tous les échantillons devraient être prélevés après un fonctionnement normal et en charge du moteur ou de l’organe mécanique surveillé, qui a permis d’atteindre la température de fonctionnement habituelle. Bien évidemment, pour des raisons de sécurité, le prélèvement sera réalisé moteur arrêté.

All samples must be taken after normal operation under load of the engine or of the mechanical component monitored allowing it to have reached its normal operating temperature. Of course, for safety reasons, the sample must be taken with the engine stopped.

11. Why are there no thresholds for the values in the reports ?

Quite simply because all engines behave differently and operate under varied conditions. Also, the type of oil used and its service time must be taken into account.

12. How long does it take to receive the kit ?

Count around 2 to 3 days to receive the sampling kit.

13. How long does it take to receive the analyses after the samples have been sent in ?

From the date when the samples are received, count around 3 days before you will receive the analysis results and the report. Therefore, you must add the time it takes to send the sample to our laboratory.

14. How can I order my oil analysis kit ?

Simply click “Order a sampling kit” in the “Individuals” section or click here. If you are already registered, simply log on with your ID and password. If not, you must create an account when you order.

15. Do I need to do an oil change to realise the sampling ?

No, there is no need to systematically change the oil to realise the sampling. We provide you with a kit containing a syringe and a hose to allow you to take a sample via the engine gauge well. Instructions provided with the kit will give you all the steps to do well done this operation.

 

16. Can we make an oil analysis on a vehicle which does not start and which did not work recently ?

The oil analysis and its interpretation depend on the quantity and the quality of the information contained in the lubricant. The non functioning of a vehicle and thus its lubricant beyond a few hours is going to affect the representativeness of the sample (settling of the solid particles for example, …). Thus, the measured parameters could be falsified and lead to an erroneous interpretation, in particular regarding wear. Nevertheless, the analysis will allow to detect some unusual situations, as a defect of air filtration, an infiltration of cooling liquid, an excessive dilution by fuel, …

 

 

This post is also available in: French